The Arizona Algorithm
by MrsVincentCrabbe
Summary: COMPLETE: A music inspired fic about Sheldon and Penny. Link to playlist in my profile.


**"The One I'm Waiting For" by Relient K**

"SHELDON!" he smirked. He knew she had found it. He turned slightly, a victorious grin on his face as he waited to hear her feet stomp across the hall. "What in hell's name is this?" she said, barely clearing the door before her tirade started. Howard, Raj, and Leonard knew to blend in with the scenery during these clashes of the titans.

"What?" he said, as innocently as he could.

"You safety pinned a note to my Hello Kitty! doll! "Caveat Emptor"? What the hell does that even mean?"

"It means "Buyer Beware" in Latin."

"Is this all about buying the wrong brand of herbal tea again?"

"I don't know, Penny," he said, his smug confidence leaking into every inflection of his voice. She pursed her lips and set one hand on her hip.

"You want a play junior rodeo, cowboy? You picked the wrong filly to wrangle." He couldn't help but think of how satisfying it would be to win this grudge match. He stood to his full height and let his fingers skim the desk absently.

"I suppose this cowboy will shall have to judge that for himself." She turned quickly on her heel, spying Leonard in the corner trying to hide behind a Green Lantern comic. "Yeah, big help you are, rodeo clown." She slammed the door behind her and Sheldon thought about how he was going to even the score.

**"Crazy For This Girl" by Evan and Jaron**

"Hey, Sheldon," Penny shouted over the sound of the cars zooming past. Her air conditioning had gone out last Friday and she didn't have the money to fix it, so she had all four windows rolled all the way down. "What's Leonard doing?" Sheldon tightened his grip on his messenger bag as the wind whipped wildly around them.

"He left for work early!"

"What?"

"I said, he left for work early! At least, that's what he told me!"

"You don't believe him?" Sheldon just sort of stopped, wondering if he should tell her. The wind was whipping her hair around in all directions, and her big white sunglasses were checking the sun. She really shouldn't be driving with those on (obstructed vision and whatnot) but he found it didn't bother him as much as it should have.

"I think he has a girlfriend!"

"What? Wait, Sheldon, why are we talking about gherkins!" He huffed and leaned in closer to her.

"No, Penny, I think Leonard has a..." Penny decelerated as she pulled off the highway, "girlfriend." She looked over at him while the stoplight glared red.

"Huh," was all she said.

**"I Am Understood?" by Relient K**

"Yahtzee!" she yelled, clapping her hands. Sheldon huffed and picked the dice up from her coffee table.

"Penny, is there a reason we played this heinous game? I mean..."

"Yes, Sheldon, I know. It's a child's game of chance with no real skill required. Why don't you do the math and figure out the probability of rolling a Yahtzee on the first try?"

"Already done that. You have a 0.07716% chance of rolling a Yahtzee on the first roll."

"Say, Sheldon," she said, changing the subject as he rolled his turn, "what do you think of this new girlfriend of Leonard's?"

"She's...alright."

"Ah, Sheldon, I saw that twitch! You don't like her. Why would you lie? You never had any problem telling me how much you don't like me."

"Now, that was a communication error. What I meant was I couldn't tolerate you in the standpoint of Leonard's significant other. On your own, I only have minor qualms."

"Oh, well, thanks!" she smiled. "But that didn't answer my question. Why would you lie?" Sheldon stopped shaking the dice (at least 23 times for maximum randomization) and looked up at Penny.

"I was under the impression I couldn't go into confidence with one of Leonard's exs about his current flame."

"I don't think one date and maybe a drunken hook up make me an ex, Sheldon." He thought about this new definition carefully before rolling the dice.

"She's terrible." Penny smiled, knowing that Sheldon wouldn't be done with his diatribe for a long time yet.

**"She Holds the Key" by Gavin DeGraw**

Penny kissed him first. She couldn't even tell herself why. It was one of the those moments that, in retrospect, made you ask yourself if you stupid or something. She just grabbed him by the neck and kissed him in the middle of one of his lectures on microbial growth on unwashed dishes. She was watching him, yellow rubber gloves and all, scrub the dishes in her sink and she couldn't stop it before it happened. She turned him around and smiled deviously before she kissed him. It wasn't a sweet first kiss but a grating, gasping demand for attention. She dragged him away from the sink, his hands dripping bubbles all over her skin that made her slick and shiny. She supposed she should have been surprised that he hadn't pushed her away yet but she wasn't. She knew she was running this show and that he was going to follow her through to the end. She thought about all the men she had given the big ol' five treatment to, but she thought of how different it was when she was really the experienced one. She smiled against his lips. He smiled back and she dragged him to her bedroom.

**"The Secret's in the Telling" by Dashboard Confessional**

He gotten very good at reading her eyes. Sometimes during Halo Night, all it took was a nanosecond glance at his hands to tell him what she wanted. She wanted to see him. She wanted to be alone with him. She wanted him. He would wait until later, after Howard and Raj had gone home and Leonard to bed and he would go to her. And she was pull him into her, meshing them together like Sodium and Chloride, two unstable ions looking to complete their outer electron shells.

It wasn't easy or simple. They didn't tell Leonard or Howard. Sheldon only kept this lie because, to him, it wasn't a lie, or even a lie by omission. This was a secret and his secrets were different than everyone else's. He would continue on with his life, wondering vaguely if she was done with him until she would brush her hand over his behind the kitchen counter and he knew she wanted to sear her kiss in his lips again, like a brand. He was quite surprise their clandestine affair wasn't written on his face with her kisses, or that his heart didn't beat her name (metaphorically). He knew her smell, her taste, her touch. He figured that one day, this secret would be a hidden past, that she would find someone else to fill the void. Until then, he was just glad to have her.

**"Edge of the World" by Emery**

Leonard found out. Of course he did. When you lived with a man like Sheldon, you learned the schedule, you knew the inflections of speech, you knew the signs. He found out by watching Sheldon leave their apartment. When Howard installed that camera, he never knew what Leonard would see. He saw Sheldon knock on the door, a real smile on his face. He saw Penny open it, her eyes glinting with a ferociousness he had seen before. She grabbed Sheldon by the shirt and kissed him with passion she had never given him. Sheldon's hands wrapped around her waist, sliding dangerously close to the hem, pushing her into the apartment. He saw her foot swing up to close the door, the pink silk of her camisole landing on the floor before the door met the jam. Leonard couldn't believe what he had seen. So he did what he could. He went to his room and listened. Sheldon didn't come home for two hours. The next day, Leonard knocked on Penny's door.

"Hey, Leonard," she greeted, the same lacey pink camisole gripping the body he had seen Sheldon touch.

"Care to update me, Penny?" he said, his voice flat and hard.

"On what?"

"You should be careful what you and Sheldon do before you close the door, Penny." He motioned towards the obviously forgotten webcam.

"God, Leonard," he pushed his way in as she tried to dig up a response. "I-"

"You were what?" he accused.

"Look here, Leonard," her anger coming to cover her embarrassment. "You have no right to judge what I do."

"Or apparently who." Her face dropped in shock that he would be so ruthless.

"What about Stephanie? Or Alicia? Huh?" He didn't have a response to that. "You think just because you don't want me to, I can't-"

"But why Sheldon!" he shouted, losing his temper for the first time in his life. He sunk down onto her couch in a stupor. "Why not some man I know I can't compete with?

"You selfish bastard," she spit.

"I know, but all I did was try to make you love me, Penny. I guess I just wasn't good enough." He got up from the couch without looking at her. "I didn't mean to love you, Penny. Look at what it's done."

**"Change Your Mind" by The Killers**

"Sheldon, I can't do this anymore," were the first words out of her mouth when she opened the door. The small smile he had only for her faded.

"Well, if that isn't foreplay," he quipped, thinking she was just wanting to talk. He let himself in past her and sat in his chair.

"No, Sheldon, this can't happen. It's going to be turn out badly."

"What makes you think that?"

"Leonard," was all she said, turning her back to him.

"What about him?"

"He knows."

"He knows? I'm sure he knows a few things. His knowledge of DC Universe comics is lacking by my standards-"

"No, Sheldon, he watched Howard's camera. He knows about us."

"Oh," he said, recognition brightening his voice strangely, "that would explain the heinous music blaring from his room at 8 p.m. this morning."

"Sheldon, you can't take this lightly!" she yelled, nerves making her sensitive to every inflection of his voice.

"Lightly? I'm taking it lightly? I have to live with him, you know. There will be three stray cats out of this one!"

"Sheldon!" she paced the floor in a huff. "We can't go on like this."

"Why not?"

"Because we hurt his feelings!"

"And that affects us how?" he had the tone of a student, waiting for the master to reveal the great answer.

"I can't see you anymore, Sheldon. It broke his heart."

"And you have no qualms about figuratively breaking mine?" he asked, no emotion betrayed in his voice.

"No!" she huffed. "As if you had a heart!" He stood suddenly.

"If you ever change your mind on that opinion, let me know."

**"The Way I Loved You" by Taylor Swift**

Penny had moved out three months later. She couldn't take the tension, the pain. She'd lost Sheldon and Leonard to this. She got an email from Raj a few months after that to tell her Sheldon had gone to some Arizona university to work with a visiting professor, one of the other 14 men who knew string theory. He had told them he would be gone for as long as the professor was in America, however long that came out to be. Leonard had moved into a smaller apartment a little closer to CalTech. Halo Night had been disbanded and Raj said that he didn't like going to the bars with Howard anymore.

Eight months after she moved out, Penny ran into Leonard at the comic book store when she went back to buy volume two for her nephew's 14th birthday. They made up over the Nightwing comics and Batman belt buckles. He apologized for putting her to a double standard and she apologized for...not for sleeping with Sheldon but for blowing up at him. He flinched at her honesty but accepted it.

And things were as they were...minus Sheldon. They danced around each other, always taking two steps towards each other and one step back. She would flirt over Chinese food and he would compliment her. He didn't date around and she respected him more. It was what it all should have been the first time.

The first night she stayed with Leonard, she knew it wasn't ever going to be like their first try. There was something between them, forever separating them.

She missed him. She missed their battles. She missed waking up to find her laundry folded. She missed the smell of herbal tea in her kitchen and the way he was stare at her when he taught her how to play chess. She missed how she would sit up late at night and think of ways to get back at him for being a dick. She missed the way he forced her to drive him around but always, somehow made it fun.

It wasn't until Leonard invited her in a second time that she knew it wasn't going to work.

**"Fourteen" by Hawk Nelson**

She had kind of left him at the doorway. He had smiled and shyly asked her if she wanted coffee. She looked at him with a sad sparkle in her eye and told him that this wasn't working. She said all kinds of lies like she knew they were always better as friends, that this was not the way she thought it should be, that he deserved more from a woman than what she could give him. He knew she was just trying to cover that he wasn't Sheldon. He gave her a kiss on the cheek, letting her know that whatever was going on, he was still her friend; that they would always be friends. He thought maybe she caught his meaning, but didn't elaborate. He went into his dark apartment, now smaller and lonelier, and thought about crying. He thought about blaring depressing music and breaking out the Ben and Jerry's that he wasn't supposed to eat. Instead, he sent an email to Sheldon, asking him when he would be home.

**"What About Now?" by Daughtry**

Penny hadn't left her apartment in three days when she heard three smart raps on her door. She thought about ignoring it but then she heard her name. There wasn't anyone in their right mind who knocked like that. Three knocks and her name. She inched closer, thinking about how this was all her wishful thinking, her mind making up that he was knocking back on 4B's door and she was answering with a kiss and smile. Three knocks and her name. She put a hand on the cold metal doorknob but couldn't find it in herself to peek through the hole or turn the knob. She could swear she heard him breathing on the other side. The door was open before she could think twice and she was looking at Sheldon.

"Hello," he said politely. She stood to the side and let him enter. "Your new apartment..." he looked around at the mess that was so characteristically her, "is nice.""Hi, Sheldon," she whispered. He thought about sitting but wasn't keen on trying out this new furniture arrangement. Instead, he stood fidgeting by her television, wiping the dust off in little fingertip swipes.

"Arizona was quite nice though the dry humidity was a terror on my comic books. I had to get a trained lab rat to come and pick me up everyday because my temporary roommate didn't seem to care whether I made it to work or not."

"Sheldon," she sighed, her body weak from the emotions of it all, "what are you doing?"

"I'm trying to make small talk to dissipate the tension. Is it not working?"

"No, sweetie, it's not."

"I feared it wasn't."

"How did you get here?"

"Leonard gave me your address and Wolowitz's dropped me off on his way to his Mother's bridge club meeting. She forgot her lucky garter belt."

"What did you come for?"

"Are we not friends? Do friends not visit each other?"

"Yeah, but ex-boyfriends don't usually show up at their ex-girlfriend's doors after a year and a half of silence like old chums."

"Oh, then I suppose I should phone Wolowitz. Yet another social faux-paus of mine," he said, a slight hint of malice and regret in his voice. He turned and made to walk out the door before Penny grabbed his wrist.

"No, Sheldon, I'm sorry...It's just..."

"I know. Perhaps I should have phoned?" She couldn't help but smile at his uncertain tone.

"Yeah," she laughed, "maybe that would have prepared me." She walked to her kitchen and set out the mugs that had become theirs during the time they had spent together. She pulled out the box of the good herbal tea and set the tea kettle to boiling.

"Oh, good, herbal tea," Sheldon usually enthusiasm dampened by the atmosphere.

"I bought it...afterward. I ended up drinking the whole box and had to buy another box. It's taken the place of my coffee now." They sat in silence until the tea kettle shrilled it's song and she set to steeped their tea. She added a little sugar and lemon to hers and some honey to his (she couldn't stop but think of his "typo" whenever she made him tea now.) She didn't tell him that she drank it because the smell reminded her of him. That she could taste him again when she sipped the liquid. She didn't tell him that she gave up coffee because it always reminded her of Penny Blossoms and the Night She Should Have Let Him Sleep. She just blew on her tea and watched him carefully do the same. Neither one knew where they had left off and where they should start. Penny let the smell of the tea waft over her and she remembered the last clear thing he said to her, "If you ever change your mind on that opinion, let me know." She looked at him, his face taut and his arms resting listlessly over the cup.

"I have changed my mind, you know. About you having a heart."

"Well, that's good."

"And I'm sorry I would have ever said that about you. I knew better." He took a calm sip.

"Apology accepted, Penny."

"And I'm sorry about Leonard."

"Yes, I suppose I pity him as well." He took another sip.

"Pity him?"

"Yes," he looked her in the eyes, "from the status reports Wolowitz sent me, you recently broke up with him."

"Oh," she had to look away, "you know about that."

"Of course."

"Do you hate me?"

"Goodness, Penny, no! I honestly don't understand people. Don't understand them one quantum at all." He finished his tea and stood, grabbing his discarded coat. The rain from early that day had returned with a vengeance and riding home on Wolowitz's scooter wasn't going to be pleasant at all. "I suppose I'll go home now. Wolowitz said he'd come back for me at eight." He checked his watch and noted the time before slipping his coat on.

"Sheldon, wait!" she walked up to him, her body moving without her mind. She grabbed his hand and made him stay to look at her. "Did you love me once?"

He didn't flinch or shy away. He didn't fidget or shuffle or try to play it off. He didn't try any Jedi mind tricks with her. He looked her in the eyes and told her the truth. "I did." She looked him in the eyes, not flushing or embarrassed, and asked him seriously, "What about now?"

"Always," it was fact, pure and simple. His voice was firm and commanding, letting her know that he had tested whatever it was he felt against all possibilities. He had watched it carefully to see if the effect faded. He had studied its consistency and its universality. Whatever it was, it was fact now, no longer just a hypothesis or a tentative, untried theory but true and unwavering fact.

"I loved you then, despite what I did. Do you believe that?"

"Yes."

"Can we...can we try again?" He watched her chew on her bottom lip, the way she always did when she was truly worried. He shut the door and set his things down.

"When cathode rays were first discovered, they thought they were made of waves because they easily passed through a sheet of metal." Penny wanted to get saucy with him for deflecting until he opened his mouth again. "What they didn't know was that the experiment was flawed to begin with. The metal was too thin and the subatomic theory too new to explain cathode ray phenomena. J.J. Thompson did a second round of experiments. He discovered the negatively charged subatomic particle he named the electron."

"What happened to J.J. Thompson?" she asked, hoping the answer was the one she wanted.

"He won the Nobel in 1906."


End file.
